9.5. Nonlinear Narrative¶

Another obvious difference with the stories in games as opposed to more traditional media, is the possibility of telling truly nonlinear stories. Traditional stories are linear:

There is only one way through a linear story, each event must be experienced in a certain order. While modern books and movies often play with the time line, jumping forward and back to tell a story out of its original chronological order, the actual telling is still a linear affair.

Some games tell a traditional linear story. In this case, the story and gameplay must be separate entities, because the story has no choices and the gameplay must include decision-making of some kind (else it is just a story and not a game). They can be thematically linked, and the story may influence gameplay (perhaps when a certain pre-scripted story element happens, it causes a new gameplay effect to come into play), but the gameplay cannot influence the story because there is only one story.

Linear stories have one major advantage over all other story structures: it is easy to apply traditional storytelling techniques, which have been developed over thousands of years. But they also have the obvious disadvantage that, due to a lack of decisions, they are not very game-like. There is a natural barrier between linear stories and game mechanics, which limits the agency the player can have within the story.

However, not all games are like this. As we’ve seen, player decisions are the core of what makes a game. Some games have a strong narrative intertwined with gameplay. For these games, it would make sense for player decisions to not only affect the mechanical outcome of the game, but to affect the narrative as well.

For some game designers, a true “interactive story” - a holodeck experience - is something of the Holy Grail of games. While there are PhD’s who are researching ways to use AI to tell truly dynamic stories, in reality, we are limited in our ability to craft games that tell stories responsive to player choice. We can roughly classify different popular approaches to interactive stories by their overall structure: what kinds of choices are available to the player, how open or constrained those choices are, and what effect those choices have on both the ongoing story and the final ending.

Branching

The first and most obvious thing to do to a linear story, if we want to add decisions, is to add choice points at various places. When the player reaches a certain point, they decide what to do, and then the story goes down one of several continuing paths until another choice point is reached. An example is the old-school Phantasy Star III for Sega Genesis; twice in the game, the main character is given a choice of which of two girls to marry (and then the story continues to the next generation of characters), leading to a total of four branches, each with its own story and its own ending.

Branching stories have the advantage of being interactive. If you include a sufficiently large number of choices and your choices cover all of the things that a player would want to do, the game can respond believably to any number of player decisions. At first, this would appear to be the ultimate solution to game narrative since it can handle just about anything.

However, there is one major drawback of using a branching story: it is expensive! With only two choices (which is not very many), the story writers of Phantasy Star III still needed to write four stories. A third choice would have had them writing eight stories, and including a mere ten choices would require writing 1024 stories! Consider the number of decisions you make as a player in a typical strategy game, and you’ll see that the amount of work to write a branching story can quickly explode into something unmanageable.

To make things worse, note that a player that goes through the game once will never even see the vast majority of content. It requires multiple replays just to see every path through the story. And, if the developers ever make a sequel to the game, they must figure out a way to reconcile all these timelines!

Parallel Paths

This describes a branching story that collapses in on itself, allowing the player to make choices but then collapsing all of them eventually into several mandatory events. In Silent Hill, for example, there are several choices the player can make that may advance the story or reveal some additional story elements along the way, and these will influence the ending. However, there are certain events that the player is forced to encounter no matter what else they have or haven’t done.

Parallel paths solve the problem of branching narrative by keeping the advantage of player decisions while still keeping the total amount of story manageable. So, at first, this would appear to be the ultimate story structure.

As you might guess, there is still a problem: since the player is forced into certain events, the overall plot arc is now essentially linear again. We have lost the player’s feeling that they are directing the story, because no matter what they do there will be certain parts of the story that are the same no matter what.

One potential solution is to have the player decisions alter the game’s ending. The player may still encounter the same plot arc, but the final outcome is determined by the choices the player made. Unfortunately, that means the relationship between cause and effect can be easily lost – the player’s decisions are (by definition) not seen until the very end, and it is often unclear what the player did to cause a certain ending.

Threaded

Alternatively, there may not be one story. Instead, the narrative, may consist of multiple plot arcs going on at once that may or may not intersect. The player then chooses which paths to follow and in what order. One example is the Elder Scrolls series of games (like Oblivion or Skyrim), where the player may follow certain storylines or ignore them entirely. At any point the player can switch which story they are advancing, perhaps starting a brand new story they just discovered.

The advantage of a threaded narrative is that it is extremely expressive. Also, the story may have multiple beginnings and middles and endings, but the player has access to all (or at least most) of them and can advance any combination of them in any order, so we have finally solved the problem of forced replays. The player can see everything there is to see with a single play-through, if they are thorough enough.

Unfortunately writing a threaded narrative is hard, because events can happen in any order, leading to the potential for the player to do things in an order that doesn’t make sense (for example, perhaps they are given a quest to assassinate a rival leader in the middle of a war, before the war actually breaks out, or after the war is concluded). The story writer must be careful to allow access to certain story events only when it would make sense to do so. Keeping track of all the variables that determine when a story event is or isn’t active can get very complicated very quickly.

Lastly, a threaded narrative runs the risk of confusing the player, if there are too many concurrent plots happening at a single time and the player does not immediately see the relationships between them. This is also a danger with books and movies that try to tell several stories at once.